1. Field of the Invention
The invention relates in general to semiconductor manufacturing and metrology applications, particularly to transactions involved in utilizing a library of profiles to determine whether a wafer product meets a certain specification.
2. Description of Related Art
Metrology is being increasingly utilized in the semiconductor manufacturing industry to ensure that the different process steps are within specifications. There are two different metrology schemes in place today: in-line metrology and integrated metrology. While in-line metrology has become standard today, wherein the product wafers are processed, transferred to a piece of metrology equipment, measured for critical dimension, profile, thickness, etc., and brought back into the line for further processing, integrated metrology is increasingly becoming state-of-the-art. In integrated metrology, the metrology equipment is integrated with the processing equipment so that measurements on the wafer are taken without needing to move the wafers out of the processing equipment, thereby increasing throughput and overall equipment efficiency.
However, even integrated metrology tools have traditionally been hardware based, expensive, and not easily re-configurable. Therefore, it is advantageous to have a new process that shift most of the complexity from expensive and slow hardware tools to sophisticated software algorithms running with relatively simple and inexpensive hardware equipment. This shift to sophisticated software tools, as illustrated in a related co-pending U.S. provisional application No. 60/233,017, now U.S. patent application Ser. No. 09/907,488, entitled xe2x80x9cGeneration of a Library of Periodic Grating Diffraction Spectraxe2x80x9d by Xinhui Nui and Nickhil Harshvardhan Jakatdar, owned by the assignee of this application and incorporated herein by reference, requires a new business model to accommodate the new user and service provider transactions involved in generating the library, managing the data, and billing the user.
In view of the above, the present invention provides the processes that leverage the use of sophisticated software algorithms in creating a library of profiles based on product specification. These libraries of profiles are compared with profiles of manufactured products to ensure that manufactured products are within the specification. A novel set of software algorithm is used with simpler hardware configurations. The software is broken into two parts: the front-end and the back-end. While the front-end can run in real time and is installed either on a metrology equipment computer or a stand-alone computer at a user site, the back-end software is very computationally intensive and requires the use of a highly parallel set of computer workstations for its operation. This separation of the computational intensive process allows for a service provider to generate and maintain the libraries offsite.